JP2574477B2 - Magnetic recording tape regulating force measuring method for recording / reproducing device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a regulating force measuring method for receiving a magnetic recording tape used in a recording / reproducing apparatus or the like from a traveling regulating means during traveling.

2. Description of the Related Art In recent years, recording / reproducing devices using magnetic recording have been widely used for VTRs and the like, and as a trend, narrower tracks and thinner magnetic recording tapes have been progressing as trends. Under these circumstances, the mechanical issues include: (1) ensuring linearity; and (2) ensuring tape running stability in order for the magnetic recording head to correctly trace the recorded track and maintain compatibility between machines. (3) Reduction of changes over time, and efforts are being made to solve the problem.

Hereinafter, a conventional method for measuring a magnetic recording tape restricting force of a recording / reproducing apparatus will be described.

FIGS. 4, 5, and 6 show a method for measuring the force of restricting the magnetic recording tape of the conventional magnetic recording and reproducing apparatus, which will be described with reference to FIG.

FIG. 4 shows a first example of measuring the regulating force around the head drum.
This is a conventional example. In FIG. 4, 2 is an upper drum, 3 is a lower drum, 4 is a magnetic recording tape, 16 is a toothpick, 17 is a finger of a researcher holding the wife, and 23 is a lead formed on the lower drum 3. .

The restricting force around the head drum is basically a pressing force of the magnetic recording tape 4 on the lead 23 formed on the lower drum 3, and there is a problem how the magnetic recording tape 4 runs correctly along the lead 23. . Conventionally, as shown in FIG. 4, a method of confirming the restricting force around the head drum is to use a jig with a sharp tip such as a wand 16 to grip the edge of the magnetic recording tape 4 while the magnetic recording tape 4 is running. It is common to lightly hold down the magnetic recording tape 4 and check the fluctuation of the magnetic recording tape 4 with the envelope 18 shown in FIG. That is, in FIG. 5, it is determined whether or not the drop occurs due to the depression 19 of the envelope 18 being pressed by the widow 16 described above.

On the other hand, FIG. 6 shows the result of measurement of the recording pattern of the magnetic recording tape 4 in the second conventional example. In this figure, reference numeral 20 denotes a recording pattern measurement result, reference numeral 24 denotes a floating portion from the lead 23, and reference numeral 25 denotes a reference line.

In FIG. 6, when the magnetic recording tape 4 is floating from the lead 23 of the lower drum 3, a portion 24 below the reference line 25 is generated, and this portion 24 fluctuates. In this example, the recording pattern measurement result 20 is used, but it can also be extracted as the fluctuation of the envelope 18.

Although not shown in the drawings, there is an example in which the magnitude of the regulating force is actually measured as the amount of wear of the regulating means by running the magnetic recording tape for several hundred hours or more.

However, in the first and second conventional examples, the state in which the tape is regulated is confirmed by an envelope or a recording pattern as a result of the regulation, and it is good or bad. The current situation is that it is only possible to judge the margin, and it is not possible to measure the margin, there is a problem that it can not be determined with specific numbers, and the method of measuring by wear is time-consuming and impractical. Had.

The present invention solves the above-mentioned conventional problems, and provides a regulating force detection method that enables the regulating force of a tape to be taken out by a physical basic force and that can evaluate the regulating force by force. The purpose is to provide.

Means for Solving the Problems In order to achieve this object, a method for measuring a magnetic recording tape restricting force of a recording / reproducing apparatus according to the present invention comprises a magnetic tape traveling restricting means for restricting the traveling of a magnetic tape provided with a relief portion in part. A rotating drum device having a magnetic tape running regulation force measuring unit for measuring a magnetic tape running regulating force generated when the magnetic tape is regulated by the magnetic tape running regulating unit, outside the rotating drum device; The measurement is performed in a state where a part of the tape running regulating force measuring means is inserted into the escape portion while being in contact with the end surface of the magnetic tape.

Operation The present invention directly detects the force that the magnetic recording tape receives from the restricting means by the restricting force detecting means by the above-described restricting force measuring method.

Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view of a method for measuring a regulating force around a drum, particularly a regulating force on a lead of a lower drum in an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a base serving as a reference, 5 denotes a regulating force detecting arm serving as regulating force detecting means, 6 denotes a semiconductor strain gauge, 7 denotes a mounting screw, 8 denotes a convex portion on the base 1, and 26 denotes a lower drum. This is the escape of the configured regulating force detection arm 5.

In FIG. 1, a fixed amount of a magnetic recording tape 4 is helically wound around a rotating upper drum 2 and a lower drum 3 having leads 23. The lower drum 3 is fixed to the base 1. On the other hand, the restricting force detecting arm 5 is of a cantilever type, and the cantilever restricting force detecting arm 5 and the semiconductor strain gauge 6 which can detect a very small force for detecting the restricting force are two.
It is glued on both sides. The regulating force detection arm 5 is fixed to the projection 8 by a mounting screw 7. A relief 26 is formed in the lower drum 3 so that the tip of the regulating force detection arm 5 enters. The magnetic recording tape 4 comes into contact with the tip of the regulating force detection arm 5. That is, since the regulating force detection arm 5 is a cantilever, it is bent by the force of the magnetic recording tape 4. A change in strain due to the bending is detected by two semiconductor strain gauges 6 attached to the front and back of the regulating force detection arm 5.

FIG. 2 is a bridge circuit showing the principle of detection by two semiconductor strain gauges 6. R1 and R4 are fixed resistors, and R2 and R3 are resistors of the semiconductor strain gauge 6. Since the semiconductor strain gauge 6 is attached to the front and back of the regulating force detection arm 5, one of R2 and R3 increases and the other decreases. The balance of the bridge circuit is lost due to the slight change in resistance, and a voltage e is generated.

Although a semiconductor strain gauge is used in the embodiment of the present invention, it goes without saying that a piezo element may be used.

Effect of the Invention As described above, according to the present invention, by providing the regulating force detecting means, it is possible to quantitatively grasp the lead of the magnetic recording tape to the drum lead, and the practical effect is very large.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a method of measuring a regulating force around a head drum according to an embodiment of the present invention, FIG. 2 is a bridge circuit diagram used in the embodiment, and FIG. FIG. 4 is a perspective view showing a method of measuring a flange regulating force around a roller, FIG. 4 is a perspective view showing a first conventional example, FIG. 5 is an explanatory view of an envelope change in the first conventional example, and FIG.
FIG. 7 is a recording pattern measurement diagram showing a conventional example of FIG. 1 ... bass, 2 ... upper drum, 3 ... lower drum, 4 ...
... magnetic recording tape, 5 ... regulating force measuring arm, 6 ... semiconductor strain gauge.

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Makoto Okuda 1006 Kazuma Kadoma, Kadoma City, Osaka Inside Matsushita Electric Industrial Co., Ltd. (56) References JP-A-60-113350 (JP, A)

Claims (1)

(57) [Claims] A rotating drum device provided with a magnetic tape running restricting means for restricting the running of the magnetic tape provided with a relief portion, and a magnetic tape when the magnetic tape is restricted by the magnetic tape running restricting means. A magnetic tape running regulating force measuring unit for measuring a tape running regulating force is provided outside the rotary drum device, and a part of the magnetic tape running regulating force measuring unit is inserted into the escape portion while abutting a part of the magnetic tape end surface. A method for measuring a magnetic recording tape restricting force of a recording / reproducing apparatus, wherein the measurement is performed in a state where the magnetic recording tape is regulated.